1. Field of the Invention
The disclosure relates to a system and a method for capturing images. Particularly, the disclosure relates to a system and a method for constructing high resolution images.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
In current optical measurement systems, if the surface of the object under test is uneven or composed of inconsistent material, the light intensity of the reflected light beam or scattering light beam on the surface will vary. Thus, it is required to use a single point capturing device with high dynamic range to obtain the accurate intensity of the reflected light beam. However, when we use the single point capturing device to measure a wide range, the device translocation needs to be controlled by a high-precision device. In addition, such devices require longer periods of time to detect larger measurement areas.
Moiré interferometry technology is currently applied for surface measurements of over 10 μm scale. Moiré interferometry technology is used to measure three dimensional appearance of the surface. The resolution of the Moiré interferometry is determined by the fineness of interference fringes. Traditionally, in order to increase the fineness of the interference fringes, scientists use certain special fringe encoding techniques such as DeBruijn space encoding technique and Gray time encoding technique. Although such techniques can provide efficient measurements, Moiré interferometry technology needs to be improved to measure objects under 10 μm scale.
In addition, when the system uses charge-coupled sensors or complementary metal oxide semiconductor sensors to measure large areas and uses high resolution technique such as white light interference technique, the measuring speed of the system may not be as fast as that of systems using Moiré interferometry technology.
U.S. Pat. No. 6,753,876 discloses a method for constructing high dynamic images for overcoming the low measuring speed. The method can adjust the light intensity, capture the image data, set up the standard image under the predetermined light intensity, and analyze whether the intensity of each pixel is over the saturation region or under the noise floor. If one pixel is over the saturation region, the method will replace it with a pixel that has lower light intensity and does not exceed the saturation region. Alternatively, if one pixel is below the noise floor, the method will replace it with a pixel that has a higher light intensity and is over the noise floor. Although the technique disclosed in U.S. Pat. No. 6,753,876 can increase measurement speed, a system and method for constructing high resolution images are still desired.